Spandrel tie



June 22, 1965 w. D. WILBUR EI'AL 3,190,606

smmnm, TIE

Filed July 15, 1962 INVENTORS Warren D. Wilbur Richard N. one

Attorney United States Patent 3,190,666 SPANDREL TIE Warren 1). Wilbur, 13379 Pastel Lane, Mountain View,

Calif, and Richard N. Tone, 1803 Mezes Ava, Belmont, Calif.

Filed July 13, 1962, Ser. No. 209,494 7 (Ilaims. (Cl. 249-27) The invention relates to spandrel ties-for connecting intersecting concrete wall and floor forms.

An object of the present invention is to provide an inexpensive spandrel tie of great holding strength which is easy to install in concrete building forms.

Another object of the present invention is to provide a spandrel tie which can be broken off cleanly in the concrete slab leaving the exposed underside with only a small opening which may be readily patched without extensive repair filling of the concrete.

The invention possesses other objects and features of advantage, some of which of the foregoing will be set forth in the following description of the preferred form of the invention which is illustrated in the drawings accompanying and forming part of this specification. It is to be understood, however, that variations in the showing made by the said drawings and description may be adopted within the scope of the invention as set forth in the claims.

Referring to said drawings (one sheet):

FIGURE 1 is a perspective view of a spandrel tie constructed in accordance with the present invention.

FIGURE 2 is an end elevation view of the spandrel tie as viewed from line 22 of FIGURE 1.

FIGURE 3 is a fragmentary cross-section of a wall and deck slip form showing a spandrel tie cast in place and a tie in place prior to pouring of the concrete.

FIGURE 4 is an enlarged fragmentary cross-section of a spandrel tie and form shown substantially along the line 44 in FIGURE 3.

FIGURE 5 is a fragmentary cross-section of a wall and deck with the forms removed showing the portion of the spandrel tie which is left in the concrete.

The spandrel tie of the present invention has been particularly designed for use in concrete poured in place building construction in the forming of wall and intersecting floor slabs as shown in the accompanying drawings. The concrete form of the present invention consists briefly of opposed interior and exterior walls 6 and 7 and a deck form 8 extending from the upper end 9 of interior wall 6 away from exterior Wall 7 and the deck 8 is formed with an opening 11 therethrough; an elongated tie member 12 having an offset portion 13 extending through opening 11 and a contiguous end 14 disposed at the underside 16 of deck 8; means 17 supporting the tie member 12 in spaced relation to the upper side 18 of deck 8; and means 21 mounted through exterior wall 7 and engaged with the opposite end 22 of the tie member 12 and including take-up means 27 for adjusting the maximum spacing of exterior Wall '7 and deck 8; tie member 12 being formed with a weakened section 24 at the offset portion 13 and adapted for breaking upon twisting of end portion 14.

Tie member 12 may be easily connected to deck form 18 by inserting end 14 through a pre-drilled opening 11 and moving tie member 12 so that end 14 is brought to bear against the underside 16 of form 8 and the offset section 13 projects through opening 11. This interlocking fit of the offset 13 with form 8 permits end 22 to swing in a wide horizontal arc and also permits some vertical movement so that end 22 may be easily connected to a take-up means 21. This interlocking fit has great holding strength; the tie having been tested up to about 3,l9,h% Patented June 22, 1965 2,000 pounds pull, which is far greater than the holding power of conventional devices.

Another important advantage afforded by the spandrel tie of the present invention is the ease with which the wall and deck forms may be stripped after setting of the concrete and the minimum damage to the wall surfaces occasioned by such stripping. With reference to FIG- URE 1, it will be noted that the weakened plane 24 is located near the top of the offset portion 13 well above the base of the chair support 17 so that this weakened plane will always be located well back into the concrete forming the deck, e.g., a minimum of /8 to /2 inch. This weakened plane is here formed by notching the Wire rod form of the member on opposite sides and twisting 011 may be conveniently accomplished by engaging the exposed end 14 of the tie, at the underside of the form, pulling down and turning the end so as to effect a twisting off of the wire at the weakened plane 24. It is to be noted that this twisting off of the tie is accomplished at the underside of the form while the concrete is still in surface contact with and supported by the upper side of the form, the form deck, conventionally /8 to plywood, affording extra support to the tie wire during the twisting oif operation. Consequently, a very clean opening 25 is left at the underside of the slab and with the removal of the tie end 14 there is no impediment or restriction whatever in removing the deck form wall 8. The tie member 12 is preferably formed of steel wire of about to 4 inch diameter.

The means 21 securing the tie member to the exterior wall 7 here includes a demountable she bolt 26 which is threadably secured to the outer end of the tie, the threaded connection being here provided by a threaded stud 36 mounted at the outer end of the tie. The conventional she bolt 26 is provided with a tapered shank 31 which projects internally from the exterior wall form 7 into the concrete wall for easy removal, the tapered shank being conventionally formed with a tapered end bore for threadably receiving stud 30.

In the interest of ease of attachment and eliminating need for rigid alignment of the parts, the connection between tie member 12 and the she bolt is here preferably provided by a loose pivotal hook and eye connection. This is accomplished by fashioning a hook 36 on the end of stud 30 and forming the outer end of tie 12 with a loop or eye 37 which may be conveniently engaged with a minimum of required precision by the hook 36. For added strength, the loop 37 may be welded closed as at 38 as best seen in FIGURE 1.

An important problem in the use of all form ties is the amount of patching of the concrete which is necessary after the removal of the forms to cover all exposed portions of the tie and to obtain a smooth, unblemished surface. Conventional spandrel ties generally rest on deck 8 and are so attached thereto as to require a great amount of patching after form 8 is removed. The spandrel tie of the present invention is completely embedded in the concrete and requires no patching except for the small hole left below weakened plane 24 when end 14 is snapped off as mentioned above. In order to secure complete embedment of snap tie 12 in the concrete, means 17 in the form of an inverted U-shaped bracket may be secured to the underside of the tie member 12 and mounted generally crosswise thereof. Bracket 17 may be formed with speced feet 41 and 42 engaging deck 8 to support tie member 12 in spaced and generally parallel relation to deck 8. The bracket is here formed of wire which has the further advantage of giving the feet 41 and 42 a circular shape of minimal area of contact with deck 8. Accordingly, no patching is necessary where the feet 41 and 42 contact deck 8 since no part of bracket 17 is perceptible from the underside 44 of the striped deck 51 except upon the closest inspection. Any danger of rusting may be eliminated by galvanizing bracket 17 or making it of rustproof material.

The placement of bracket 17 in close relation to offset portion 13 increases the holding power of tie member 12 in form 8 by holding offset portion 13 perpendicular to form 8; thus evenly distributing the shear forces exerted by offset portion 13 against the sides of opening 11 in deck form 8.

Another important feature of the present invention is the spandrel ties great anchoring strength in the concrete after the concrete deck 51 and wall 32 have been poured. This great anchoring strength makes it possible to use slip forms, as shown in FIGURE 3, to make a second pour on top of deck slab 51 and wall 32. Spandrel tie 12 and the J-hook 33 are cast in concrete deck 51 and wall 32, and she bolt 52 is removed leaving opening 35 in the wall. When forms 6 and 7 are moved skyward for the pouring of the next upper floor, another she bolt 52 may be re-engaged with the threaded end 30 of the J-hook, by insertion in the wall opening 35 so as to cinch up the lower end of the form 7. Tight cinching of form 7 to surface 57 is most important in order to prevent an unsightly overlap of concrete at the new pour line 53. The great anchoring strength of the present spandrel tie 12 which makes possible first class slip form work is rovided by the casting in the concrete of loop 37, chair 17, and a portion 56 of offset 13.

We claim:

1. In a concrete form, opposed interior and exterior walls and a form deck extending from the upper end of said interior wall away from said exterior wall, said deck being formed with an opening therethrough, an elongated tie member having an off-set portion extended through said opening and a contiguous end disposed at the under side of said deck, means supporting said tie member in spaced relation to the upper side of said deck, and means mounted through said exterior wall and engaged with the opopsite end of said tie member and including take up means for adjusting the maximum spacing of said exterior wall and deck, said tie member being formed with a weakened section at said off-set portion adapted for breaking upon twisting of said first mentioned tie member end.

2. In a concrete form, opposed interior and exterior walls and a form deck extending from the upper end of said interior wall away from said exterior wall, said deck being formed with an opening therethrough, an elongated tie member having an off-set portion extended through said opening and a contiguous end disposed at the under side of said deck, means supporting said tie member in spaced relation to the upper side of said deck, a threaded stud mounted on the opposite end of said member in the space between said walls for casting in the concrete wall formed thereby, and means mounted through said exterior wall and having a shank threadably engaged with said threaded member end and including takeup means for adjusting the maximum spacing of said exterior Wall and deck, said shank being tapered for removal from the formed concrete wall, said tie member being formed with a weakened section of said off-set portion adapted for breaking upon twisting of said first mentioned tie member end.

3. In a concrete form, opposed interior and exterior walls and a form deck extending from the upper end of said interior wall away from said exterior wall, said deck being formed with an opening therethrough, an elongated tie member having an oflF-set portion extended through said opening and a contiguous end disposed at the under side of said deck, means supporting said tie member in spaced relation to the upper side of said deck, the opposite end of said tie member being formed with a loop, a member having a hook at one end engaged with said loop and a threaded end extended toward said exterior wall and adapted for casting in the concrete wall to be formed between said form walls, and means mounted through said exterior wall and having a shank threadably engaged with said threaded member end including take up means for adjusting the maximum spacing of said exterior wall and deck, said shank being tapered for removal from the formed concrete wall, said tie member being formed with a weakened section of said off-set portion adapted for breaking upon twisting of said first mentioned tie member end.

4. In a concrete form, opposed interior and exterior walls and a form deck extending from the upper end of said interior wall away from said exterior wall, said deck being formed with an opening therethrough, an elongated tie member having an off-set portion extended through said opening and a contiguous end disposed at the under side of said deck, an inverted U-shaped bracket secured to the under side of said tie member and mounted generally crosswise thereof and having spaced feet engaging said deck to support said member in spaced and generally parallel relation thereto and said first-named end in engagement with the under side of said deck, and means mounted through said exterior wall and engaged with the opposite end of said tie member and including take-up means for adjusting the maximum spacing of said exterior wall and deck, said tie member being formed with a weakened section of said off-set portion adapted for breaking upon twisting of said first mentioned tie member end.

5. A concrete form as characterized in claim 4 wherein said U-shaped bracket is positioned adjacent to said off-set portion and cooperates with the positioning of said weakened section so as to dispose the latter above said deck whereby said off-set portion will be broken back into the concrete floor slab formed on said deck upon twisting off of said first mentioned tie member end.

6. A spandrel tie comprising, an elongated tie member having end portions connected to an intermediate offset portion, said end portions extending in substantially spaced parallel relation and in opposite directions from said offset portion, attaching means provided on one of said end portions, supporting means carried by said lastnamed end portion having a perpendicular dimension extending from said last-named end portion in the same direction as and being less than the perpendicular dimension of said offset portion, and said offset portion being formed with a weakened section adapted for breaking upon twisting of the other of said end portions.

7. A spandrel tie as set forth in claim 6 wherein said attaching means comprises a loop formed as an integral part of said end portion, and said supporting means comprises an inverted U-shaped member secured to said end portion generally crosswise thereof and having spaced depending feet.

FOREIGN PATENTS 786,970 11/57 Great Britain.

OTHER REFERENCES Universal Products Catalogue, 902, page 34.

MICHAEL V. BRINDISI, Primary Examiner.

ROBERT F. WHITE, Examiner. 

1. IN A CONCRETE FORM, OPPOSED INTERIOR AND EXTERIOR WALLS AND A FORM DECK EXTENDING FROM THE UPPER END OF SAID INTERIOR WALL AWAY FROM SAID EXTERIOR WALL, SAID DECK BEING FORMED WITH AN OPENING THERETHROUGH, AN ELONGATED TIE MEMBER HAVING AN OFF-SET PORTION EXTENDED THROUGH SAID OPENING AND A CONTIGUOUS END DISPOSED AT THE UNDER SIDE OF SAID DECK, MEANS SUPPORTING SAID TIE MEMBER IN SPACED RELATION TO THE UPPER SIDE OF SAID DECK, AND MEANS MOUNTED THROUGH SAID EXTERIOR WALL AND ENGAGED WITH THE OPPOSITE END OF SAID TIE MEMBER AND INCLUDING TAKE UP MEANS FOR ADJUSTING THE MAXIMUM SPACING OF SAID EXTERIOR WALL AND DECK, SAID TIE MEMBER BEING FORMED WITH A WEAKENED SECTION AT SAID OFF-SET PORTION ADAPTED FOR BREAKING UPON TWISTING OF SAID FIRST MENTIONED TIE MEMBER END. 